I'm not that familiar with the trails in the Manistee National Forest...yet, but I just got back from spending the last two days in the Leota area. There are not only alot of fairly easy trails, there are so many that I got lost for four hours trying to find my buddies campsite and I thought I knew exactly where I was going (got to get a GPS)! Most are very easy for a stock vehicle, but I got turned around by a few mud holes, mainly because I was the only vehicle and no winch.
You can definetly run the Leota area for a few days and run miles and miles of trails. If you decide to run up into the area and want another vehicle along drop me a line and maybe we can meet up.